At the same time, the new revelations are fueling calls by lawmakers for an extensive inquiry into controversial Bush administration programs, and Mr. Obama now faces a challenge making good on his promise to protect from legal jeopardy those intelligence operatives who acted within Justice Department interrogation guidelines.

Some members of Congress and human rights lawyers are likely to press for new disclosures about the period of several months in 2002 when C.I.A. interrogators began interrogating Abu Zubaydah, a Qaeda operative captured in March of that year, before the Justice Department had officially endorsed the interrogation program.

Representative John Conyers Jr., the Michigan Democrat who is the chairman of the House Judiciary Committee, on Friday raised the prospect of prosecuting senior Bush administration officials and Justice Department lawyers who authorized the harsh interrogations.

“If our leaders are found to have violated the strict laws against torture, either by ordering these techniques without proper legal authority or by knowingly crafting legal fictions to justify torture, they should be criminally prosecuted,” Mr. Conyers said in a written statement.

In a Wall Street Journal op-ed article published Friday, two senior Bush administration officials were highly critical of the White House decision to declassify the memos.

“Its effect will be to invite the kind of institutional timidity and fear of recrimination that weakened intelligence gathering in the past, and that we came sorely to regret on Sept. 11, 2001,” wrote Michael V. Hayden, a former C.I.A. director, and Michael B. Mukasey, a former attorney general.

The American Civil Liberties Union, whose lawsuit forced the release of the Justice Department memos on Thursday, plans to press the Justice Department to release other classified documents from the Bush era, including a 2004 C.I.A. inspector general’s report that gives details about C.I.A. officers who exceeded Justice Department interrogation guidelines.

“These are the first dominoes,” said Jameel Jaffer, an A.C.L.U. lawyer. “It will be difficult for the new administration to now argue that other documents can be lawfully withheld.”

Leon E. Panetta, the C.I.A. director, raised that very prospect in recent meetings with White House officials as he pressed his case to withhold delicate details from the public release of the Justice Department memos.

In a statement to the C.I.A. employees on Thursday, Mr. Panetta said the release of the Justice Department memos “is not the end of the road on these issues.”

“More requests will come — from the public, from Congress, and the Courts — and more information is sure to be released,” he said.

Some Republicans in Congress criticized the White House for declassifying the details of the interrogation techniques, saying that the revelations would allow Qaeda operatives to train to resist the rigors of captivity.

Agency officials are now worried that the revelations could play into demands by lawmakers for extensive investigations on Capitol Hill and elsewhere. Officers of the C.I.A., they said, could even be called to testify in public about their role in detention and interrogation operations.

One focus of scrutiny could be the period from April to August of 2002, when C.I.A. officers interrogated Abu Zubaydah before the Justice Department gave its official written endorsement of the interrogation program. According to a Justice Department inspector general’s report, F.B.I. officials who watched some of the interrogation sessions in a Thailand safe house reported that the C.I.A. interrogators had used several harsh techniques.

The Justice Department is also expected make public an internal ethics report that officials say is highly critical of top Bush lawyers who drafted the interrogation memos, including Jay S. Bybee, John C. Yoo and Steven G. Bradbury. Legal experts said there is an outside chance that the report could include referrals to state bar associations, which have the power to reprimand or disbar their members.

Republican lawmakers and some Bush administration officials, including former Vice President Dick Cheney, have already criticized Mr. Obama for banning all of the C.I.A.’s “enhanced interrogation techniques.”

The techniques were both lawful and effective, they said, and putting unnecessary limits on intelligence officials could make the United States more vulnerable to future attacks.

The effectiveness of the C.I.A. techniques is now the subject of a review by the Senate Intelligence Committee. White House officials have generally supported this inquiry for several reasons. Unlike the idea of an independent commission proposed by Mr. Conyers, which would be a very public affair, the intelligence committee’s review is being carried out behind closed doors. The committee’s final report, if it is to be made public, could be as much as a year away.

A version of this article appears in print on , on page A10 of the New York edition with the headline: Release of C.I.A. Interrogation Memos May Open the Door to More Revelations. Order Reprints|Today's Paper|Subscribe